1. Field of the Invention
The present invention relates to a video and/or audio recording apparatus, and more specifically relates to a digital video and/or audio recording apparatus for recording video and/or audio data to a recording device.
2. Description of the Background Art
Conventionally, digital audio recording devices for recording music and other audio data include the Digital Audio Tape (DAT) recorder, and, more recently, audio recording devices using the Mini Disc (MD) recording medium. Audio recorders using the CD-R (Compact Disc-Recordable) medium have also been developed and are currently available.
Digital video recording devices for recording movies and other moving picture data (including the associated audio data) include recording devices using the Digital Video Cassette (DVC) medium. Video recorders using the DVD-RAM (Digital Versatile Disc-RAM) medium are also being developed.
Audio recording devices using semiconductor memory are also used in answering machines and similar devices, while video recording devices for recording still picture similarly using semiconductor memory are used in digital cameras.
Such conventional video and/or audio recording devices record the video and/or audio data to a recording medium having a finite capacity, which varies depending upon the device. A problem with such devices, therefore, is that when the recording medium becomes filled to capacity while recording is in progress, an interruption occurs in video and/or audio reproduction.
This problem is addressed in many such devices by, for example, enabling the user to select a xe2x80x9cstandardxe2x80x9d or xe2x80x9clong playxe2x80x9d mode to change the total recordable time of the medium. This causes the recording device to change the compression rate used for video and/or audio encoding according to the user-selected recording mode and the writing speed to the physical media, thus changing the effective recording time.
Even with this method, however, there is no change in the fact that the maximum recording time is predetermined, and the above-described problem is not truly resolved.
Japanese Patent Laying-Open No. 6-259099 (1994) teaches an audio recording apparatus for hierarchically coding and recording audio data to semiconductor memory.
FIG. 24 is a block diagram showing the major parts in a conventional audio recording apparatus as taught in the above-noted Patent Application Publication (referred to below as the conventional audio recording apparatus). As will be known from FIG. 24, this conventional audio recording apparatus comprises: a hierarchical encoder 240 for hierarchically encoding audio data supplied thereto; recording unit 242 for recording data output from the hierarchical encoder 240 to the semiconductor memory 241, which is integral to the recording unit 242; and a recording controller 244 having a recording management database 243, which it uses for controlling the recording unit 242.
The operation of the above-described conventional audio recording apparatus is described next below with reference to FIG. 24.
The hierarchical encoder 240 first hierarchically codes audio data input thereto. That is, the hierarchical encoder 240 codes the audio data using an orthogonal transformation or subband coding method, divides it into a plurality of frequency bands, and hierarchizes the frequency bands (that is, assigns a priority level to the frequency bands) such that a low frequency band is assigned to a low hierarchical layer (a high priority level), and a high frequency band is assigned to a high hierarchical layer (a low priority level). Alternatively, frequency bands that are audibly difficult to discern are assigned to a high hierarchical layer for masking.
The recording unit 242 then records the data output from the hierarchical encoder 240 to the semiconductor memory 241 in which the data is divided into groups of blocks in each hierarchized layer.
The recording controller 244 monitors the recording unit 242 during this process to measure the amount of data recorded to the semiconductor memory 241, detects where in the semiconductor memory 241 the data (code blocks) for each layer is stored, and generate to hold a recording management database 243 indicating this detected address information. The amount of data stored to the semiconductor memory 241 and the capacity of the semiconductor memory 241 are compared, and when the recorded data exceeds the available capacity, the recording controller 244 controls the recording unit 242 as follows.
When the data to be recorded exceeds the storage capacity of the semiconductor memory 241, the recording controller 244 refers to the recording management database 243 described above and instructs the recording unit 242 to continue recording data output from the hierarchical encoder 240 by overwriting data to an address in the semiconductor memory 241 where data associated with a higher layer is recorded. As a result, output data from the hierarchical encoder 240 continues to be recorded to the semiconductor memory 241 while leaving intact the lower layer data that was recorded before the storage capacity of the semiconductor memory was exceeded.
It should be noted that audio data recorded as described above to the semiconductor memory 241 can be reproduced by again referring to the recording management database 243 stored by the recording controller 244 to first read and decode lower layer data recorded before the semiconductor memory storage capacity was exceeded, and then read and decode data recorded after the storage capacity was exceeded.
This is because lower layer data can be decoded with reference only to, that lower layer, but higher layer data must be decoded with reference to a lower layer. Therefore, even if a higher layer is lost due to data overwriting, the remaining lower layer data can still be decoded. (It should be noted, however, that the sound quality of the reproduced audio drops because of high frequency band elimination.)
As described above, the conventional audio recording apparatus hierarchically codes audio data supplied thereto for recording to semiconductor memory 241. When the semiconductor memory 241 becomes full, audio data is recorded by overwriting previously recorded data from a high hierarchical layer. This method is referred to below as xe2x80x9chierarchical overwrite recording.xe2x80x9d As a result, recording continues even when the semiconductor memory 241 becomes full, and there is, therefore, no interruption in the reproduced audio. Furthermore, if recording is completed before the semiconductor memory 241 is filled, high quality audio can be reproduced.
However, semiconductor memory 241 typically does not have enough capacity for practical use as a video and/or audio data recording medium. Applications for such conventional audio recording apparatuses are therefore limited to applications having a relatively short recording time and not requiring particularly high sound quality, including, for example, answering machines as noted above, recorders for language study practice (such as English conversation as a second language), and toys (such as a toy parrot) for mimicking a person""s voice.
The present inventors therefore invented a method for realizing the above-noted hierarchical overwrite recording method using a large capacity, random access, disc-type recording medium (such as a floppy disk, fixed disk, MD, CD, or DVD; such media are below referred to as xe2x80x9crecording disksxe2x80x9d).
Using this method, it is possible to record video and/or audio data for a movie or music for which both a long recording time and high quality reproduction are required without the reproduced video and/or audio being interrupted when the recording disk becomes full during recording. In addition, if recording is completed before the recording disk is filled, recording can be completed so that the recorded video and/or audio data can be reproduced with high quality.
It should be further noted, however, that recording data to a disk generally involves some mechanical operation, such as moving the recording head and spinning the recording disc. As a result, the seek time is long compared to a semiconductor memory 241. Because the above-noted conventional audio recording apparatus uses a semiconductor memory 241, however, the seek time is so short that it can be effectively ignored, and no particular considerations are therefore taken with respect to the seek time.
The following problems can therefore result when recording video and/or audio data to a recording disc using a method such as that employed in the above-noted semiconductor memory-based conventional audio recording apparatus. That is, if the input data is recorded by overwriting previously recorded data associated with a higher layer, the complicated mechanical operation required to access the overwrite address can incur a long seek time depending upon where the data to be overwritten is recorded. As a result, a delay can occur in the recording process. Furthermore, even if a delay in the recording process does not result, power consumption is increased by the mechanical operation.
In addition, when the above-noted conventional audio recording apparatus writes twice, for example, the reproduced sound quality in the first and second parts of a recording will not necessarily be the same. This is also true when data is written three times, that is, the sound quality will not necessarily be the same in the beginning, middle, and end parts of a recording.
Therefore, an object of the present invention is to provide a video and/or audio recording apparatus and method for hierarchical overwrite recording of video and/or audio data using a recording disc without an accompanying complicated mechanical operation.
A further object of the present invention is to provide a video and/or audio recording apparatus and method whereby video and/or audio data recorded to a recording disc by means of hierarchical overwrite recording can be recorded so that, when data is recorded to a first recording stage from the start of recording until the disc is full, and is thereafter recorded to a xcex3th recording stage (where xcex3=2, 3, . . . ), the quality of the reproduced video and/or audio gradually deteriorates as hierarchical overwrite recording progresses from recording stage 1 to recording stage 2, recording stage 3, and so forth, and the quality of the reproduced video and/or audio corresponding to recording stage 1 to recording stage xcex3 is the same when hierarchical overwrite recording ends at recording stage xcex3.
A first aspect of the present invention is directed to a video and/or audio recording apparatus for recording input video and/or audio data, comprising:
a hierarchical coding means for hierarchically coding input video and/or audio data so that data in a bottom layer is independently decoded, and data in a layer other than the bottom layer is decoded by referring to lower layers;
a block generating means for generating a plurality of blocks of a uniform size from data in each hierarchically coded layer obtained by the hierarchical coding means;
a recording means for recording a block generated by the block generating means to a recording medium, the recording medium being rewritable, randomly accessible, accompanied by mechanical operation in recording, and contained in the recording means; and
a recording control means for controlling the recording means;
wherein the recording control means:
until the recording medium becomes full, controls the recording means to record a plurality of blocks generated by the block generating means to the recording medium so that blocks are arranged in a linear and consecutive sequence; and
after the recording medium becomes full:
selects a plurality of lower layer blocks as blocks to be recorded from blocks generated by the block generating means;
selects a plurality of higher layer blocks from a block sequence on the recording medium as blocks to be overwritten; and
controls the recording means to record a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence
By means of this first aspect of the invention, it is possible, using a rewritable and randomly accessible recording medium which is accompanied by mechanical operation in recording, to record video and/or audio data by means of hierarchical overwrite recording without an accompanying complicated mechanical operation.
A second aspect of the present invention is directed to a video and/or audio recording apparatus according to the first aspect of the invention, wherein the recording control means:
controls the recording means to record a plurality of blocks in a predetermined hierarchical sequence when recording blocks generated by the block generating means; and
when selecting a higher layer block from a block sequence on the recording medium as a block to be overwritten, refers to an overwrite block table, the overwrite block table recording a location of a block to be overwritten in block sequence.
By thus holding an overwrite block table in which the overwrite block locations in the block sequence are recorded, it is possible by means of this second aspect of the invention to easily select the overwrite blocks by referring to this overwrite block table.
A third aspect of the present invention is directed to a video and/or audio recording apparatus according to the second aspect of the invention, wherein the predetermined sequence has a cycle; and
the overwrite block table records a location of a block to be overwritten in one cycle.
By means of this third aspect of the invention, it becomes sufficient to store a small overwrite block table recording information for only one block cycle.
A fourth aspect of the present invention is directed to a video and/or audio recording apparatus according to the first aspect of the invention, wherein the recording control means:
controls the recording means to record a plurality of blocks in a sequence of xcex2 block cycles in a first recording stage until the recording medium becomes full, where xcex2 is the least common multiple of {xcex1, xcex1xe2x88x921, xcex1xe2x88x922, . . . , 2} and xcex1 is a desirable constant integer value of two or greater; and
in a xcex3th recording stage (where xcex3=2, 3, . . . , xcex1) after the recording medium becomes full:
selects a block from layer 1 to layer (xcex2/xcex3) when selecting a lower layer block as a block to be recorded from blocks generated by the block generating means;
selects a block from layer (xcex2/xcex3+1) to layer (xcex2/(xcex3xe2x88x921)) when selecting a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
when recording the lower layer block to be recorded by overwriting to the higher layer block to be overwritten in sequence from a block near a beginning of the block sequence, controls the recording means to record the layer 1 to layer (xcex2/xcex3) blocks by overwriting to the layer (xcex2/xcex3+1) to layer (xcex2/(xcex3xe2x88x921)) blocks in a sequence of (xcex2/xcex3) block cycles.
By means of this fourth aspect of the invention, the block sequence on the recording medium when recording stage xcex3 is completed evenly contains blocks recorded in recording stage 1 to recording stage xcex3.
It is therefore possible to record video and/or audio data such that the quality of the reproduced video and/or audio gradually deteriorates as hierarchical overwrite recording thus progresses from recording stage 1 to recording stage 2 and recording stage xcex1, and the quality of the reproduced video and/or audio is the same in every recording stage irrespective of the recording stage at which hierarchical overwrite recording ends in the range recording stage 2 to recording stage xcex1. In other words, if hierarchical overwrite recording ends at recording stage xcex3, the quality of the video and/or audio reproduced for recording stage 1 to recording stage xcex3 will be same for every stage.
A fifth aspect of the present invention is directed to a video and/or audio recording apparatus for recording input video and/or audio data, comprising:
a hierarchizing means for hierarchizing input video and/or audio data so that data of a highest priority is hierarchized to a bottom layer, and as data priority decreases, the data is hierarchized to a higher layer;
a block generating means for generating a plurality of blocks of a uniform size from data in each hierarchized layer obtained by the hierarchizing means;
a recording means for recording a block generated by the block generating means to a recording medium, the recording medium being rewritable, randomly accessible, accompanied by mechanical operation in recording, and contained in the recording means; and
recording control means for controlling the recording means;
wherein the recording control means:
until the recording medium becomes full, controls the recording means to record a plurality of blocks generated by the block generating means to the recording medium so that blocks are arranged in a linear and consecutive sequence; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from blocks generated by the block generating means;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
controls the recording means to record a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
By means of this fifth aspect of the invention, it is possible, using a rewritable, randomly accessible recording medium which is accompanied by mechanical operation in recording, to record video and/or audio data by means of hierarchical overwrite recording without an accompanying complicated mechanical operation.
A sixth aspect of the present invention is directed to a video and/or audio recording apparatus according to the fifth aspect of the invention, wherein the recording control means:
controls the recording means to record blocks in a predetermined hierarchical sequence when recording blocks generated by the block generating means; and
when selecting a higher layer block from a block sequence on the recording medium as a block to be overwritten, refers to an overwrite block table, the overwrite block table recording a location of a block to be overwritten in block sequence.
By thus storing an overwrite block table in which the overwrite block locations in the block sequence are recorded, it is possible by means of this sixth aspect of the invention to easily select the overwrite blocks by referring to this overwrite block table.
A seventh aspect of the present invention is directed to a video and/or audio recording apparatus according to the sixth aspect of the invention, wherein the predetermined sequence has a cycle; and
the overwrite block table records a location of a block to be overwritten in one cycle.
By means of this seventh aspect of the invention, it becomes sufficient to store a small overwrite block table recording information for only one block cycle.
An eighth aspect of the present invention is directed to a video and/or audio recording apparatus according to the fifth aspect of the invention, wherein the recording control means:
controls the recording means to record a plurality of blocks in a sequence of xcex2 block cycles in a first recording stage until the recording medium becomes full, where xcex2 is the least common multiple of {xcex1, xcex1xe2x88x921, xcex1xe2x88x922, . . . , 2} and xcex1 is a desirable constant integer value of two or greater; and
in a xcex3th recording stage (where xcex3=2, 3, . . . , xcex1) after the recording medium becomes full:
selects a block from layer 1 to layer (xcex2/xcex3) when selecting a lower layer block as a block to be recorded from blocks generated by the block generating means;
selects a block from layer (xcex2/xcex3+1) to layer (xcex2/(xcex3xe2x88x921)) when selecting a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
when recording the lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence, controls the recording means to record the layer 1 to layer (xcex2/xcex3) blocks by overwriting to the layer (xcex2/xcex3+1) to layer (xcex2/(xcex3xe2x88x921)) blocks in a sequence of (xcex2/xcex3) block cycles.
By means of this eighth aspect of the invention, the block sequence on the recording medium when recording stage xcex3 is completed evenly contains blocks recorded in recording stage 1 to recording stage xcex3.
It is therefore possible to record video and/or audio data such that the quality of the reproduced video and/or audio gradually deteriorates as hierarchical overwrite recording thus progresses from recording stage 1 to recording stage 2 and recording stage xcex1, and the quality of the reproduced video and/or audio is the same in every recording stage irrespective of the recording stage at which hierarchical overwrite recording ends in the range recording stage 2 to recording stage xcex1. In other words, if hierarchical overwrite recording ends at recording stage xcex3, the quality of the video and/or audio reproduced for recording stage 1 to recording stage xcex3 will be same for every stage.
A ninth aspect of the present invention is directed to a video and/or audio recording apparatus for recording input video and/or audio data, comprising:
a block generating means for generating a plurality of blocks of a uniform size from input video and/or audio data;
a recording means for recording a block generated by the block generating means to a recording medium, the recording medium being rewritable, randomly accessible, accompanied by mechanical operation in recording, and contained in the recording means; and
a recording control means for controlling the recording means;
wherein the recording control means:
until the recording medium becomes full, controls the recording means to record a plurality of blocks generated by the block generating means to the recording medium so that blocks are arranged in a linear and consecutive sequence; and
after the recording medium becomes full:
selects a block to be recorded from blocks generated by the block generating means;
selects a block from a block sequence on the recording medium as a block to be overwritten; and
controls the recording means to record a block to be recorded by overwriting to a block to be overwritten in sequence from a block near a beginning of the block sequence.
By means of this ninth aspect of the invention, it is possible, using a rewritable, randomly accessible recording medium which is accompanied by mechanical operation in recording, to record video and/or audio data by means of fragmented overwrite recording without an accompanying complicated mechanical operation.
A tenth aspect of the present invention is directed to a video and/or audio recording apparatus according to the ninth aspect of the invention, wherein the recording control means, when selecting a block from a block sequence on the recording medium as a block to be overwritten, refers to an overwrite block table, the overwrite block table recording a location of a block to be overwritten in block sequence.
By thus storing an overwrite block table in which the overwrite block locations in the block sequence are recorded, it is possible by means of this tenth aspect of the invention to easily select the overwrite blocks by referring to this overwrite block table.
An eleventh aspect of the present invention is directed to a video and/or audio recording apparatus according to the tenth aspect of the invention, wherein the location of a block to be overwritten has a cycle; and
the overwrite block table records a location of a block to be overwritten in one cycle.
By means of this eleventh aspect of the invention, it becomes sufficient to store a small overwrite block table recording information for only one block cycle.
A twelfth aspect of the present invention is directed to a video and/or audio recording apparatus according to the ninth aspect of the invention, wherein when selecting a block from a block sequence on the recording medium as a block to be overwritten in a xcex3th recording stage (where xcex3=2, 3, . . . , xcex1; and xcex1 is a desirable constant integer value of two or greater) after the recording medium becomes full in a first recording stage, the recording control means selects a total of (xcex2/xcex3) blocks, including (xcex2/(xcex3(xcex3xe2x88x921))) blocks recorded in each recording stage 1 to (xcex3xe2x88x921) as overwrite blocks in each cycle of xcex2 blocks, where xcex2 is at least common multiple of {xcex1, xcex1xe2x88x921, xcex1xe2x88x922, . . . , 2}.
A thirteenth aspect of the present invention is directed to a video and/or audio recording apparatus according to the ninth aspect of the invention, wherein when selecting a block from a block, seqence on the recording medium as a block to be overwritten in a xcex3th recording stage (where xcex3=2, 3, . . . , xcex1; and xcex1 is a desirable constant integer value of two or greater) after the recording medium becomes full in a first recording stage, the recording control means selects a total of (xcex3xe2x88x921) blocks, including 1 block in each recording stage 1 to (xcex3xe2x88x921) as overwrite blocks in each cycle of blocks, where the number of blocks in each cycle is equal to the least common multiple of {xcex1, xcex1xe2x88x921, xcex1xe2x88x922, . . . , 2}.
By means of the twelfth and thirteenth aspects of the invention, the block sequence on the recording medium when recording stage xcex3 is completed evenly contains blocks recorded in recording stage 1 to recording stage xcex3.
It is therefore possible to record video and/or audio data such that the quality of the reproduced video and/or audio gradually deteriorates as fragmented overwrite recording thus progresses from recording stage 1 to recording stage 2 and recording stage xcex1, and the quality of the reproduced video and/or audio is the same in every recording stage irrespective of the recording stage at which fragmented overwrite recording ends in the range recording stage 2 to recording stage xcex1. In other words, if fragmented overwrite recording ends at recording stage xcex3, the quality of the video and/or audio reproduced for recording stage 1 to recording stage xcex3 will be same for every stage.
A fourteenth aspect of the present invention is directed to a method for recording input video and/or audio data, comprising the following steps:
a hierarchical coding step for hierarchically coding input video and/or audio data so that data in a bottom layer is independently decoded, and data in a layer other than the bottom layer is decoded by referring to lower layers;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchically coded layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
By means of this fourteenth aspect of the invention, it is possible to record video and/or audio data by means of hierarchical overwrite recording to a recording medium without an accompanying complicated mechanical operation.
A fifteenth aspect of the present invention is directed to a method for recording input video and/or audio data, comprising the following steps:
a hierarchizing step for hierarchizing input video and/or audio data so that data of a highest priority is hierarchized to a bottom layer, and as data priority decreases, the data is hierarchized to a higher layer;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchized layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
By means of this fifteenth aspect of the invention, it is possible, using a rewritable, randomly accessible recording medium which is accompanied by mechanical operation in recording, to record video and/or audio data by means of hierarchical overwrite recording without an accompanying complicated mechanical operation.
A sixteenth aspect of the present invention is directed to a method for recording input video and/or audio data, comprising the following steps:
a block generating step for generating a plurality of blocks of a uniform size from input video and/or audio data; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a block to be recorded from generated blocks;
selects a block from a block sequence on the recording medium as a block to be overwritten, and
records a block to be recorded by overwriting to a block to be overwritten in sequence from a block near a beginning of the block sequence.
By means of this sixteenth aspect of the invention, it is possible to record video and/or audio data by means of fragmented overwrite recording to a recording medium without an accompanying complicated mechanical operation.
A seventeenth aspect of the present invention is directed to a recording medium for recording a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a hierarchical coding step for hierarchically coding input video and/or audio data so that data in a bottom layer is independently decoded, and data in a layer other than the bottom layer is decoded by referring to lower layers;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchically coded layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks,;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
An eighteenth aspect of the present invention is directed to a recording medium for recording a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a hierarchizing step for hierarchizing input video and/or audio data so that data of a highest priority is hierarchized to a least significant layer, and as data priority decreases, the data is hierarchized to a higher layer;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchized layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks,;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
A nineteenth aspect of the present invention is directed to a recording medium for recording a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a block generating step for generating a plurality of blocks of a uniform size from input video and/or audio data; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a block to be recorded from generated blocks;
selects a block from a block sequence on the recording medium as a block to be overwritten; and
records a block to be recorded by overwriting to a block to be overwritten in sequence from a block near a beginning of the block sequence.
A twentieth aspect of the present invention is directed to a program supply method for supplying over a network a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a hierarchical coding step for hierarchically coding input video and/or audio data so that data in a bottom layer is independently decoded, and data in a layer other than the bottom layer is decoded by referring to lower layers;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchically coded layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear, consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
A twenty-first aspect of the present invention is directed to a program supply method for supplying over a network a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a hierarchizing step for hierarchizing input video and/or audio data so that data of a highest priority is hierarchized to a bottom layer, and as data priority decreases, the data is hierarchized to a higher layer;
a block generating step for generating a plurality of blocks of a uniform size from data in each hierarchized layer; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to the recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a lower layer block as a block to be recorded from generated blocks;
selects a higher layer block from a block sequence on the recording medium as a block to be overwritten; and
records a lower layer block to be recorded by overwriting to a higher layer block to be overwritten in sequence from a block near a beginning of the block sequence.
A twenty-second aspect of the present invention is directed to a program supply method for supplying over a network a computer-executable program for recording input video and/or audio data, the program achieving on the computer an operating environment comprising the following steps:
a block generating step for generating a plurality of blocks of a uniform size from input video and/or audio data; and
a recording step for recording a generated block to a recording medium, which is rewritable, randomly accessible, and accompanied by mechanical operation in recording;
wherein the recording step for recording a generated block to a recording medium:
records a plurality of generated blocks to the recording medium so that blocks are arranged in a linear and consecutive sequence until the recording medium becomes full; and
after the recording medium becomes full:
selects a block to be recorded from generated blocks;
selects a block from a block sequence on the recording medium as a block to be overwritten; and
records a block to be recorded by overwriting to a block to be overwritten in sequence from a block near a beginning of the block sequence.
These and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction the accompanying drawings.